The military has foiled an attempt by Manuel Zelaya, the ousted president of Honduras, to return to his country, but clashes between his supporters and security forces have led to at least two deaths.
The main airport in Tegucigalpa, the Honduran capital, was the scene of an extraordinary drama on Sunday as thousands of Zelaya supporters gathered outside in anticipation of his announced arrival.
But soldiers blocked the runway with a military vehicle and refused the aircraft carrying Zelaya and his close aides permission to land.
Zelaya told Venezuelan network Telesur from his aircraft that the pilot flew low and circled around the airport but decided that landing was "totally impossible".
Military aircraft were in the flight path and soldiers and military vehicles were blocking the runway, he said.
After vowing to try again to re-enter Honduras on Monday or Tuesday, Zelaya headed to El Salvador to discuss his next move with other Latin American leaders.
On the ground, the crowd tried to break into the airstrip, prompting riot police to fire tear-gas shells as well as live rounds, resulting in the first known fatalities of the crisis that has engulfed the Central Asian country since the June 28 coup.
One of the victims was a 10-year-old boy. Several Zelaya supporters were also injured in the violence.
Honduran emergency services confirmed that a child had been killed and a Red Cross spokesman said it was treating about 30 people for injuries.
Soldiers later closed the Tegucigalpa airport. The nightly curfew imposed by the military-backed interim government was moved up by three hours, sending demonstrators home early.
Describing the day's developments, Al Jazeera cameraman Alfredo Delara said the demonstration had been relatively peaceful until a group of about 100 protesters, mostly youth, started throwing stones and bottles at security forces and tore down a fence separating the two sides.
Troops responded by firing their weapons for about 10 minutes, dispersing most of the crowd, he said.
But some protesters continued to confront the troops and our cameraman witnessed at least one soldier pointing his weapon directly at the protesters and at least one person going down after being shot.
Lucia Newman, Al Jazeera's Latin America editor, said Sunday's fatalities could be a turning point for the interim government, who had been boasting for days that the coup against Zelaya had been bloodless.
Now that there had had been bloodshed, a lot of people were probably thinking that things were getting much messier than they had bargained for and support for the coup may begin to ebb, she said.
The interim government had warned Zelaya that, should he tried to return, he would be arrested for 18 alleged criminal acts, including treason and failing to implement more than 80 laws approved by congress since taking office in 2006.
Zelaya was removed from power as he was about to press ahead with a non-binding referendum that his domestic critics said was aimed at changing the constitution to enable him to run again for office.
In the run-up to Sunday's airport drama, leaders of the interim government gave a televised news conference and called for dialogue with the Organisation of American States (OAS).
The OAS, a hemispheric bloc dedicated to strengthening political co-operation and reforms, suspended Honduras's membership of the body on Saturday.
"The Republic of Honduras has communicated to the representative of the OAS in Tegucigalpa that it is willing, with the aim of conducting conversations in good faith with a mission of representatives of the secretary general," Martha Lorena Alvarado, the interim deputy foreign minister, said.
Neverthelesss, tensions between Honduras and several of its neighbours sympathetic to Zelaya continue to be high.
Roberto Micheletti, who was sworn in as Honduras' president after the coup, said on Sunday that the Nicaraguan military was moving towards the two countries' shared border.
"We have been informed that in the sector of Nicaragua some troops are moving toward the border," he said.
"I would like, respectfully to ask our Nicaraguan brothers not to cross our borders as we are gong to defend them."
A Nicaraguan army spokesman said that the Honduran accusations were "totally false".
Francisco Dominguez, head of the centre of Brazilian and Latin American studies at Middlesex University in the UK, said he did not believe that there was any basis to the claims that the Nicaraguan military could become involved.
"I think it is a very desperate manoeuvre to divert attention from the crisis they are in the middle of," he told Al Jazeera.
"I have never seen a regime so isolated as this one."
However, Alvarado, the Honduran minister, defended her government's actions.
"We are tying to put this country in order because Mr Zelaya wanted to have a replica of Venezuela. If you have ever been to Venezuela, you can foresee our future for the next 20 years," she told Al Jazeera in a phone interview.
"People have the right to demonstrate but they do not have the right to disrupt with rocks, destroying everything and defying the police."